Only one third of a search engine is devoted to fulfilling search requests. The other two thirds are divided between crawling (sending a host of single-minded digital organisms out to gather information) and indexing (building data structures from the results). Ed's job was to balance the resulting loads.

When Ed examined the traffic, he realized that Google was doing more than mapping the digital universe. Google doesn't merely link or point to data. It moves data around. Data that are associated frequently by search requests are locally replicated—establishing physical proximity, in the real universe, that is manifested computationally as proximity in time. Google was more than a map. Google was becoming something else. ...